OAKLAND — It's possible Yankees first baseman Mark Teixeria will sit again Sunday as he works to recover from a strained back muscle that sidelined him before Saturday's 5-1 loss to the A's.

Manager Joe Girardi and Teixeira each said his availability would be determined Sunday morning. The Yankees' off day Monday could entice Girardi to sit his 33-year-old one more day.

The player and the coach each said they were hopeful Teixeira was only suffering from muscle spasms. He didn't undergo any tests.

Neither thought the injury was too serious, however.

"I don't think so," Girardi said.

Teixeira has been bothered by injuries all season.

His surgically repaired right wrist kept him out of a handful of games in June. He also spent 15 days on the disabled list with a strained hamstring. Additionally, Teixeira has complained of tired legs and a tight groin.

The muscle was tight when Teixeira woke up Sunday and, despite heavy treatment, it felt much worse after he participated in a full pre-game batting practice session, Teixeira said.

Teixeria said he's suffered from muscle spasms in the past, but not in the shoulder.

"You get them in your neck and your back and behind your shoulder sometimes," he said. "And sometimes you can play through them and they're not that big of a deal. Other times it's kind of debilitating. (Saturday) it locked up pretty good."

The Yankees could have used Teixieira in Saturday's loss. He's had a ton of success against Scott Kazmir, who eventually earned the win. In his career, Teixeira is 11-for-20 off Kazmir with two homers, four doubles and eight walks.